Process and apparatus for coking pitch



' F. PUENING. PROCESS AND APPARATUS FOR COKING PITCH.

APPLICATION FILED JAN-12,1918.

1 2 79 Patented 001;. 4, 19211 H SHEETSSHEET I.

F. PUENING.

PROCESS AND APPARATUS FOR COKING PITCH. AIPPLICATION FILED JAN- 12. 1918.

ag m, mm m, 41,11Q2L g? n SHEETS-SHEET '2.

F. PUENJNG. I

PROCESS AND APPARATUS FOR CO KING PITCH. APPLIQATION FILED um. 12, 1918.

Patented Oct. 4?, 192111 I I SHEETS-SHEET 3.

Patented Oct 4, 19211 H 8HEETSSHEET 4.

F. PUENING. PROCESS AND APPARATUS FOR COKING PITCH.

APPLICATION FILED IAN-12,1918- F. PUENlNG.

PROCESS AND APPARATUS FOR COKING PITCH.

APPLICATION man JAN. 12, 191B.

1,392,79n Patented 00$- 4, 1921,.

El SHEETS-SHEET 5.

F. PUENING.

PROCESS AND APPARATUS FOR coma PITCH.

APPLICATION FILED JAN. 12. 1918. 1,3923% Patented Oct. 4, 19211 Hlhi KZWW67ZZ0Z? F. PUENING.

PROCESS AND APPARATUS FOR come PITCH.

APPLICATION FILED JAN. 12, l9l8- Patented Oct 4, 1921A mum H .SHEETSSEET 7.

F; PUENING.

PROCESS AND APPARATUS FOR COKING PATCH. APPLICATION men JAN. 2, 191a.

F. PUENING.

PROCESS AND APPARATUS FOR COKING PITCH. APPLICATION FILED JAN- !2. 191a.

1,392 8?@ Patented Oct. 4, 1921.

, n susars snmj Fizz/6 J95 Hillllh 05 ZQQ F. PUENING.

PROCESS AND APPARATUS FOR COKING PITCH.

APPLICATION FILED JAN. 12, 1918. 1,392,799 Paten'befl 00a, 4, 119210,

I I SHEETSSHEET I0.

, 4'" v H I a w fig @725 F. PUENING. PROCESS AND APPARATUS FOR come PITCH. APPLICATION FILED JAN- I2, I9IB. g g yg Patented Oct. 4, 1921.

ll SHEETS-SHEET 1 I.

i To all whom it'may concern aranr oesica.

111mm PUENING, or CHICAGO, ILLINOIS, ASSIGNORTO AMERICAN TAR PRODUCTS COMPANY, or GHICAGO ILLINOIS, A conronarron or DELAWARE' PROCESS AND APPARATUS FOR COKING PITCH;

Be it known that I, FRANZ PUENING, a citizen of the United States, residing at Chicago, in the county ofCook and State of Illinois, have invented certain new and useful Improvements in Processes and Apparatus for Coking Pitch, of which the following is a specification.

. y invention relates mare particularly to the coking of coaltar pitch, though it is also applicable to the treatment of other similar liquid hydro-carbons-and materials. Prior to my invention various efforts have been made to coke coal tar pitch, but with no commercial success. In the efforts heretofore made stationary retorts of large size have been employed and it has been customary to heat them to the high temperature required to make a good coke. Where such retorts have been made of cast iron they have shown a tendency to crack under the' strain of expansion and contraction, due 'to the heat changes, and brick and fire clay retorts have been equally unsatisfactory because they leak and part of the charge is lost. Steel retorts in the ,practice heretofore attempted under the high temperatures quickly. corrode and are destroyed. Moreover, when the pitch is heated in the furnaces and retorts heretofore used, there is a tendency to foam at a certain stage of the heating process, which can only be avoided by very careful firing. Furthermore, in such furnaces, because of the high temperature which has to be maintained toward the close of the coking operation, and for many hours previous thereto, there is a great waste of heat in hot stack gases. Also much time was lost in permitting the coke to cool down before removal from the retorts, and much labor was required for this operation.

In'my improved process and apparatus the coking is carriedout in a series of retorts or receptacles which are movable within the furnace and after being filled with the pitch to be coked, carried gradually from a point of relatively low heat near the stack I of the furnace to a point of maximum heat ature where the maximum temperature is required, and transmitting their heat to receptacles containing pitch at successively lower temperatures, finally heating the sup- Specification of Letters Patent Patented @a. a, 19 21.

Application filed January 12, 1918. Serial No. 211,546.

ply tank of pitch to keep it suficiently liquid and escaping to the stack with but little of the r heat. Thus by my improved process zft-ndl' apparatus I effect a great economy in In the accompanying drawings I have dis closed a preferred formof apparatus for carryingput my process, and described the same 1n the following specification. It is to be understood, however, that the specific d1sclosureis for the purpose of exemplification only and that the scope of the inventlon is defined in the followin claims, in which I have endeavored to distinguish it from the prlor art, without, however, rellquishing or abandoning any portion or feature thereof.

Referring to the drawings, Figure 1 is Y a plan view, with parts broken away, of one end of a plant 111..Wl1l0l1 myinvention is embodled; and Fig. 1 a similar view of the other extremity of the ,plant. Fi 2 1s a similar view on an enlarged scale O? an intermediate portion of the plant. Fig. 3

is an elevation, partly in section, of substantially the same part of the plant shown in. Fig. 2, and Fig. 3 a similar viewof the end of the plant toward and including the stack; Fig. 3 is a vertical section similar to Figs. 3 and 3 of the fire-box end of the plant, and to. the right of that portion thereof shown in. Fig. 3 Fig. 4 is a transverse vertical section taken on the line 44 of Fig. 3; Fig. 5 is an enlarged end elevation; and Fig. 6, aside elevation of the saine portion of the plant; Figs. 7 and 8 elevations at right angles to each other of dotted lines; Fig. 10 a transverse vertical section on-line 1O10 of Fig. 10; Figs.

11 and 11 together represent a vertical longitudinal section on line 1111 of Fig. 13-Fig. 11 showing the end of said apparatus near the entrance thereto, and Fig. 11 the exit end thereof; Fig. 12 is a vertical, transverse section on the line 12-12 of Fig. 11*; Fig; 13 a similar section on the line 13-43 of Fig. 11 showing also the connection from one of said receptacles for deliverdetail .on an enlarged scale; Fig. 17 is a plan View of one of the pitch receptacles or retorts; Fig. 18 a. vertical section of a detail thereof on the line 18-18 of Fig. 17

Fig. 19 a similar section on the line'1919 of Fig. 17; Fig. 20 a perspective of a detail; Fig. 21 a perspective of a receptacle body on a reduced scale, and Fig.22 a simisary to vary the temperature or firing of the' lar viewof a modified form thereof; Figs. 23 and 24 a side elevation partly in section, and transverse section respectively of a detail; Fig. 25 a perspective of another detail; Fig. 26 a perspective of another detail; and Fig. 27 a plan of a deta il partly .in section. v

Each part is identified by the same reference characterwherever it occurs throughout the several views.

One of the main features of my invention is that the operation of the rocess is substantially continuous, so that 1t is not necesfurnace but it is maintained as nearly. as

possible thesame as long as the furnace is in operation. I during treatment is contained in a series ofreceptacles and the furnace is so arranged As above stated 'the pitch and designed that these receptacles may be traversed through the furnace from the stack end to the fire-box end, the-pitch being submitted thereby to gradually increasing temperature until it is completely coked, when the receptacle containing the same is removed from the. furnace and the coke dumped by mechanism which will be here inafter described. During the coking operation the receptacles or retorts are covered and the matter volatilized is carried by a pipe into a, conduit extending alongside the furnace from which the various products are recovered. The retorts are suspended from a continuous track along which they travel through the furnace and after mping are returned .to the entrance-end of the furnaceand prior to again enterin the same are charged with new batches o pitch.

With this general understanding of the construction, will now describe the apparatus in detail. Referring more particularly to Figs. 1 to 4 inclusive, the furnace comprises a long flue or passage 26, along which the pitch retorts travel, having a firebox 27 at one end thereof which communicates indirectly with the stack 28 at its other end. The fire-box proper 27 is located beneath the passage 26 and communicates therewith by means of a flue 29 extending some distance beneath the passage 26 and connecting therewith at its end 30 and also by means of some short connecting flues 31, 32 at suitable intervals so that the heat of the fire-box is distributed sufiiciently to avoid undesirable concentration at any one portion of the passage. Flues 31, 32 may be controlledby brick dampers 31 32 to properly distribute the heat. The construction of fire-box and flue by which the products of combustion are fed to the pot-heating chamber or passage is such that, by

properly conducting the firing, combustion is confined to the fire-box and main flue,

only products ofcombustion in which no substantial amount of air or oxygen is intermingled being permitted to come in contact wlth the pots or receptacles whereby destruction of the latter by oxidation isgreatly retarded or substantially prevented.

The furnace is constructed of usual materials such as fire-brick, brick and cement. The dimensions of the passage 26 depend upon the size of the retorts 33 to be used therein, it being necessary that the passage be made of a diameter sufliciently greater than that of the retorts to provide for the rearward passage of the gases about the latter. The fire-brick side walls 34, 34 of the passage project inwardly at their upper edges as at 35, 35 and are surmounted by adjustable iron or other plates 36, 36 (see Figs. 4 and 25) which plates are thickened at their inner edges 37 and may be adjusted toward and from the center of the passage by means of rods 39, 39 connected at suitable intervals in openings 40, 40 (see Fig. 25), spaced along said plates and provided with nuts 42, 43 on opposite sides of the stationary angle irons 44, extending parallel to said passage. The purpose of these plates 36, 36 is to form a close joint with flanges 45 secured to the upper portions or rims of the retorts or receptacles 33 and coacting sheet of steel 45 and an intermediate layer of heat insulating material, and each flange is secured to an annulus 46 which is riveted to the upper edge of the body portion 47 of its respective receptacle. The annulus 46 is of thicker metal than the body of the pot or retort and the flange is secured thereto by L-shaped straps 48, 48, 48 through which certain rivets 49 connecting the annulus and the body portion of the receptacle are passed, said straps being secured to the flange by bolts 50.

As the pitch cokes it expands or crowds upward and advantage is taken of this fact to provide for 'the ready dumping of the pots after the cokingis complete, the pots being made"with this end in view of such a flare or taper thatthe upward movement of the material during coking carries it away slightly from the walls. As the pots are subjected to a high temperature whrle loaded, during the process, and would therefore, unless precaution were taken to the contrary, be apt to change shape so as to make it difficult to get the formed coke out of them, they are made of theshape shown more'particularly in Figs. 21, 22, which is that they would tend to assume under such conditions of load and temperature. The bottom portions of the pots are roundedor approximately spherical, the curve diminishing higher and gradually merging into an elongated conical surface. This shape is therefore approximately-that of a catenary in cross section. When the pot is reversed thesolid residue falls out in one piece.

Assho'wn in Figs. 21 and 22 the retorts or pots may be struck up out of sheet steel and formed of two halves 51, 51 welded together at their abutting edges 52 as in Fig.

21 or they may be made of, three sections, to wit, the longitudinal sections 53, 53, and an end or bottom section 54, as in Fig. 22. The upper edge ofthe annulus 46 of each bucket is preferably grooved or depressed as at 55 to receive an annular rib 56 of similar cross section formed upon the cast metal top 58 whereby a close joint between said top and annulus is effected. In order to secure the top of the pot, pairs of ears 59 are formed at suitable intervals about the top and projecting above the same between which ears are pivoted plates 60 (see Fig. 20) by means of bolts 61 passing through slots 62 in said plates. The plates are also formed with perforations 63, whichwhenthe cover is in place on the pot project between lugs 64 at the upper ends. of the straps 48 and are pivoted to said straps by.

pins 65 extending through perforations in said ears and through holes 63. At their outer ends latch plates 60 are also formed with openings 66 to which links 67 arepivoted by, bolts 68, said links forming a part of the supporting means for said covers or receptacles as hereinafter described. It is to be observed that the weight of the cover and pot suspended from these links forces the inner ends of plates 60 downwardly against the cover, slots 62 permitting the necessary play and therefore the cover is: maintained in the closest possible contact with the annulus 46 during the coking operation. Four of the "angle straps 48 are provided with the ears above described for l the plates 60 but intermediate straps 48 gether are without such lugs but straps 48 48 which secure the flange and annulus toare formed with outwardly-extending ears 72 perforated at 7 3 for a purpose which will appear. Cover 58 is also formed with a filling opening 74 and plug 75 and with an outlet nozzle 76 which receives the end of gooseneck 77 by which the volatile products are coveyed to the trough for receiving them described below.

As heretofore observed these pots or retorts are traversed along the passage 26 with their flanges substantially in contact with packing plates 36 at the sides and with the similar flanges of adjoining pots. Thus the escape of the hot gases and products of combustion from the passage through the top thereof is substantially prevented. In order to substantially prevent the escape of products of combustion from the entrance end of the passage the latter is formed for a distance to accommodate two successive pots into a narraw trough 78 of a cross section to substantially fit against the bodies of the pots passing therethrough (see Fig. 10) which thus block the outward passage of the hot products of combustion through said end of the passage and because of the length of the constricted end of the passage and the manner'of feeding the pots, at least one pot is.always blocking said constricted end. A downwardly directed flue 7 9 communicates with the passage 26 adjacent the constricted end thereof and merges into a horizontal flue 80 connected to a riser 81 by which the products of combustion and gases are carried to a heating chamber 82 surrounding the supply tank 83 for the pitch. The tank 83 is spaced from the-walls of said chamber by brick-work 84 to permit the passage of gases around said tank and the chamber is connected by a short flue 85 with the stack 28, a damper 86 in the last said flue serving to control the escape of the products of combustion. By the construction just described I have provided for the entrance of the pots into the-passage 26 without the escape of the heating gases which are carried through lines 79, 80 and 81 to the chamber for maintaining the supply of pitch in a sufiiciently heated condition to lnsure the required fluidity, thus substantially using all the heal generated in the fire-box.

The hot products of combustion'and gases are prevented from escaping and air from entering at the exit end of the passage not only by a similar construction of said passage to fit .the pots as at 87 (see Figs. 8 and 10) but by a door or shutter 88 which further seals the o ening. The door is mounted in a metallic continuation of said passage. comprising slatted metal. side walls 89 continuing the brick sidewalls of the furnace and a bottom 90, said walls and bottom being supported on suitable uprights 91 raised upon th cement or other foundations 92. Said door is pivoted at 93 between the side walls and counterweighted at 94 and shaped as shown in Fig. 10 so that it yields when a receptacle is pressed against it but cotiperates with said receptacle in maintaining the seal of the passageat that end until the receptacle'is carried out of contact therewith. The manner of pivoting the door is shown in detail in Fig. 26, said door being secured to a shaft 95 by means of brackets 96. Uprights 91 are braced by members 97 connected thereto and to the.

cross-beam 98 secured to the foundations of the furnace. It will be obvious that as each receptacle is carried against the door by the means to be presently described, the door yields until the receptacle passes beyond it and then resumes its normal position, closing the end of the passage. By the described construction waste of the hot gases is substantially prevented and furthermore ac-.

cess of air to the heating chamber is avoided and thus the atmosphere of the chamber maintained neutral or reducing, avoiding or track is carried. The track is supported on Lbeams103, and trolleys 104 (see Fig. 28), which carry the respectiveretorts or pots, are each supported on the track by trucks 105v which are pivoted at 106 to the opposite ends of each said trolley and provided with rollers 107 shaped to engage the track. By-

pivoting the trucks the wheels thereof are enabled to follow 'the track about the turns thereof. Each trolley atjits opposite ends .is provided with a depending angular member 107 rigidly secured thereto, the laterally bent ends 108 of which members engage and support a bridge bar 109 which extends immediately below and parallel to the track. From these bridge members the pots and their respective covers are supported. As

- seen in Fig. 27 a pair of 'transverse members 110, 111 are secured to the bridge bar, memmember 111 pivoted thereto at 112, and both members bent at an angle of 45 degrees at their ends as at 113, and perforate at 114 to receive the sup orting members for the respective pots. Ks heretofore stated the pivoted plates 60 of which there arefour to each pot and cover are suspended by pairs of links 67. Each pair of links is connected to a turn-buckle 115, the up er end of which carries a hook 116 and t e four hooks of each pot are inserted in the corresponding holes 114 in the transverse member carried by the corresponding trolley. By reason of the transverse member 111 being'pivoted the pot is evenly sustained notwithstanding wise of the furnace ing mechanism until, the coking operation havin let e115 ber 110 being rigidly secured thereto and slight variations in the lengths of the supporting links or members.

The trolleys may be fed along by hand or by any suitable mechanism. In the particular construction shown in the drawings I have employed an endless chain 117 im- 117 is carried by sprockets 118, 119 and driven by sprocket 120 which in turn receives its motion from a motor 121' driving said sprocket through pinion 1 22 and gear 123. Each trolley carries a pivoted dog 124 journaled upon the longitudinal member 125 of said trolley which dog is so weighted that its end 126 normally projects upwardly into the path of the links of said chain to be enga ed and driven thereby in one direction on the dog yielding for relative motion between the trolley and chainin the other direction.

The several pots are suspended from the track by their respective trolleys except during the comparatively brief intervals during which they are dumped. After dumping in a manner to be presently described each pot is returned to its respective trolley and fed rearward on the limb of the loop ;of track at one side of the furnace until it comesinto charging position at the entering end of the furnace passage adjacent the tank 83. The

tank 83 has an outlet 127 with a movable spout 128 and controlled by a valve 129. As each receptacle or pot is brought into fillin position the plug 75 is removed from the fil in opening 74 and the spout 128 inserte in the latter and the desired'iamount of pitch run into the retort. The retort is then pushed by hand or otherwise into the entering end of the furnace passage, the dog on the trolley running under the chain until it is engaged by one of the links thereof.

From this time the pot is slowly fed lengthby the chain and its drivbeen completed, it arrives at the outof the passage for dunrfiing. As shown more particularly in Fig. 3, the

track is extended considerablybeyond the endiof the furnace so as to permit the pots :to travel in a rightline until they escape the door. Afterthe door has been released each pot is fed forward by'hand or otherwise disengaging the dog on the trolley from the chain. and carried around the end of the loop into dumping position shown more particularly in Fig. 3. Up to this point the pot is suspended from its trolley but it is now released therefrom by mechanism to be presently described and dumped and then returned to its trolley support. The dumping mechanism is best shown in Figs. 5 to 8,

inclusive. It comprises a corset or harness eeasae 130 which receives the pots successively, supports them so that they may be disengaged from their respective covers and trolleys, dumps them and returns them to their covers and trolleys. Referring now to- Figs. 7' and 8, in which the corset or harness is shown on a somewhat enlarged scale it will beseen that this apparatus comprises avertical U- shaped member 131 of a shape roughlycorresponding to a vertical section of the pots and formed of iron strap or bars riveted together, and a pair ofhorizontal U-straps 132, 133, rigidly secured thereto, the construction being such that the corset may be appliedlaterally to the respective retorts and the vertical U brought in substantially diametrical position thereon with the hori- -Zontal Us abutting against the exterior of the pot. The ends 134 of the vertical member of the corset are provided with inwardly projecting lugs 135, 136 which are spaced apart and perforated in register with each other, the perforations being so spaced that when the corset is in place upon a pot the perforations in the ears 135, 136 are in registry with the perforations 73 in the outwardly turned lugs 72 on said pot. I rovide a pair of locking bars 137, 137 which are guided for vertical movement in guide lugs 138, 139, mounted on cheek-plates 140 on the respective ends of the vertical U member, the upper ends of rods 137 being' .turned over or reversed so that when said rods are in their lowered position as shown in Figs. 7 and 8, the reversed ends 141 enter the perforations in lugs 135, 136, and if the harness is in position on a pot said locking rods also project through theperforations in the lugs on said pot between lugs 135 and 136 thus securing the harness or corset to the pot. Springs 142 compressed between lugs 139- and collars 143 on said rods urge the latter toward their lowermost position and thereof. 1 v

The harness thus described is suspended by cars 144 thereon and cables 145, the latter being so controlled that the harness may be raised or lowered to adjust it to a pot and moved laterally with respect thereto.

The cables 45 which are two in number pass upwa'r from the ears 144 and over sheaves 146, 146 to drums 147, 147 upon a transverse shaft 148. Said .sh ft is mounted prevent accidental displacement.

- vers 167 are a shaft 161 turned by a handle 162. By suitably operating the cables 1'45 and 158 the corset may be brought into propenengagement with the pot to be dumped and secured thereto by the engagement of "the rods 131 with the lugs of said pot. When this has been accomplished the pot is slightly raised to transfer the weight thereof from the trolley and from the pivoted plates 60 and the pivot pins 65 are then withdrawn from the lugs 64 (see Figs. 17 and 18) whereby the pot is released from its cover and trolley. The, pot is then lowered by means of the cables 145. I In order to reverse the pot for dumping it I employ a pair of cables 163 which extend over sheaves 164, 164 to the larger drums 165, 165 upon the shaft 148,

and are wound thereon in a direction the reverse of the winding "of cables 145. The other ends of the cables 163 are secured to the eyes 166 attached to the respective upper ends of a pair of levers 167 pivoted at 170, 170 to the corset. Said levers are connected together at their opposite ends by a rod 168 and loop strap 169 respectively, to form a latch frame for holding the lower end of the pot in the corset during dumping, and are so overweighted that they normally occupythe position shown in dotted lines in Fig. 7 in which the strap loop 169 is lowered out of the way so that the corset may be readily applied to a pot to be dumped or removed therefrom. When, however, the cables 16.3 attached to the eyes 166 are tautened by revolving the shaft 148 in the proper direction, the levers swing about. their pivots to bring the strap 169 against the pot which is thus tightly held in the corset and prevented from separating therefrom at its lowerjend. Further draft upon the cables 163, which is accompanied by a suitable slackening of .the cables 145, transfers the weight of the pot to the former cables permitting it to reverse into the position shown in dotted lines in Fig. 6. It is desirable, however, to lock the swinging frame comprising the levers 167 when in the position to grasp the pot and for this purpose I have provided a pair of latch pins 171, which are slidably mounted in perforations in levers 167 and brackets 172 thereon and normally held in their inner positions by springs 173. The vertical loop 131 is provided with side plates 174 to which lepivoted at 170 and the respective edges 0 which are engaged by said latch pins when the pivoted frame is in the position shown in full lines in Fig.- 7 to avoid accidental displacement of the pivoted frame.

In order to take care of the volatile products given off during the coking process I provide alongside the passage for the pots or retorts a trough 175 into which'the products of distillation are led. The trough as shown in Fig. 4 is generall rectangular in cross section and may exten throughout the whic there is one for eac retort cover attached to the outlet 76 thereof. The first.

length of the furnaces-being rovided with the end walls 176, 177. (See igs. 11 11".) Intermediate the ends of the trough and extending through the portion thereof corre ends of said links=or suspension rods being.

connected to clamps 181 which embrace the lower edges of the respective beams and the trough is maintained in proper lateral position by spacing bar 182 connected to uprights 101. The gases and vapors from the pitch are conveyed from the retortsto said trou h and 'hood by the oose-necks 77 of joint 77 of the 'goose-neck'is inclined upwardly from the cover and adapted to extend to a point above the upper edge of the adjacent wall of the trough when the retort with the cover thereon is in position in the passage of the furnace, and at upper end is provided with a horizontalswivel connection 183 by which it connects to the dependingmember 184 of said goose-neck. The lat ter is of a length to reach beneath the surface of the liquid in the trough where it carries a shoe 185 which extends under the edge of the hood as at 186. (See Figs. 23, 24). The shoe is in the form of an inverted shallow trough curved in cross section, closed at one end by an end wall 187 and open at'theother end 188 beneath the hood.

In order to get the goose-neck into the trough over the end of the latter and to guide it beneath the hood I provide within the trough a pair of guides 189, 190, the lower of which extends over the opposite ends of the trough at 191, 192. At the entering end of the trough the guide 190 is extended beyond the trough and curved downward as at 193, so that when thefshoe on the goose-neck approaches the trough it strikes the inclined end of the guide and the depending section of the goose-neck turns upon the swivel joint previously described permitting the shoe to ride upon the guide and down into the trough. Beneath the hood the guide 19 isv subs nt ly h i ntal and. be-

"of the trough. The

yond the hood toward the exit end of the trough the guide again inclines upwardly to turn the depending section of the gooseneck into position to escape the end wall 177 guides 189, 190 may be supported in any suitable manner andare shown as suspended fromthe convenient cross beams 102 by the uprights 194 (see Figs. 14, 15) to which they are attached by suitable brackets 195, 196. 'Within the trough the guides may be supported from the walls of the latter by the brackets 197. (See Fig. 12.) The upper guide 189 extends from the lower inner edge of the forward end of the hood a short'distance toward the entering end of the trough, the forward end of said guide being upwardly inclined at 198 to ease the shoes into position between the parallel portion of guides 189, 190. It is important in order to prevent back pressure on the gases and vapors which would cause leakage that the depending end of the gooseneck and the shoe be immersed as little in the liquid as is consistent with conveying the products under the edge of the hood. The

adjacentedge 199 of the hood is therefore somewhat higher than the more remote edge 200 thereof, and provided with an outwardly turned flange 201 against which the shoe bears, and the latteris maintained in close contact with said flange by means of a foot 202 loosely bolted to a cross piece "203 within the hood and depressed at its free end by a spring 204 intermediate the end of said foot and said cross piece- The spring surrounds a bolt 205 extending through openings in said foot and cross piece. The foot 202 bearson the lower guide 190 and the pressure of the spring is suflicient to maintain the shoe against the lower edge 186 of the hood. The distillates in the trough may be maintained at the desired level by properl locating the overflow 206 from the troug and vapor pressure within the hood is avoided by means of the drop-.ofi pipe 207 which receives the mixture of uncondensed vapors and fixed gases and leads it to a condenser 208 in which the va ors are condensed and separated from the xd gases. The latter alone or together with any desired amount of the vapors may be used for. firing the furnaces or for any other purpose, r The operation of the apparatus has been substantially described in connection with the description of its construction. A brief resume. of they operation may be given as "follows: The pots prior to their entries into the heatingpassage are successively filled to the proper level from the tank. Necessarily the unheated .cover' projecting be ond the passage and exposed to the atmos ere provides a cooling instfumentality. t is necessaif'ly to ofl"set the cooling efl'ect of the cover su ciently to raise the temperature of the surface of the pitch to that atwh'ich it may neeaave ultimately coke, and therefore the pots are not completely filled but only to such a level as will leave a heating area of side wall above the level of the pitch which will counteract the cooling eflect of the cover and cokethe pitch. Each pot as it is filled is carried forward around the bend into the heated passage, the pots being so crowded that their flanges are in contact so that one of the potsv always forms an obstacle to the passage of the heating gases through the constricted entering end of the passage. As soon as the potenters the passage its trolley is in position to be engaged by the constantly moving endless chain which thereafter moves the pot forward until it reaches the exit end of the heatin passa e and pushes past the door which yie ds un er its pressure and comes opposite the corset of the dumping mechanism. The corset is then applied to the pot, the pot detached from its cover by removing the pins 65 and the pot then dumped in the manner heretofore described. Aft er the pot has been reversed and the charge dropped therefrom, the pot is swung back in position and attached to its cover and then again carried by its trolley and pushed by hand or otherwlse to'the fillin tank where it is again filled and the operatlon repeated.

It will now be apparent that by slowly feeding the pots along the passage 26 therefor they are exposed to a slowly but constantly rising temperature. Thus the action 'on the contents of the pots at any particular time is substantially uniform throughout and objectionable foaming and boiling of the pitch is prevented and opportunity is given thus slowly increasin the temperature of the.

mass in each pot coklng of the outer layers is retarded until substantially the whole is approaching the coking point. This is important from an economical point of view because the rigid vesicular coke is a very poor conductor of heat compared to the pitch in its molten condition and the heat therefore may be conveyed to the inner portions of the ing the passage, a series of pots movable lon gitudinally of the passage, said pots being closed to the heating gases within the passage and provided with means for efl'ecting discharge of distillate, means for charging said pots with pitch and for moving them through the passage, and means for successively discharging the pots.

. 3. An apparatus for coking pitch comprising an elongated passage, means for supplying said passage at one end with hot products of combustion, means for withdrawing the hot products of combustion from the other end of the passage, a series of pots movable'flongitudinally of the passage, individual covers for the re spective pots, means for conducting away from the pots the products of volatillzation, means for charging said pots with pitch and for moving them through the passage.

4. An apparatus for coking pitch, comsage therethrough, a series of pitch pots closed to the heating gases in the passage and provided with means for efi'ecting discharge of distillate, means for supporting the pots in the passage and traversing them along the passage, a fire-box at one end of said passage, and a flue for the escape of products of combustion at the other end of the passage,

5. An apparatus for coking pitch, comprising a furnace having an elongated pas-- prising a furnace having an open-ended open-top passage, a fire-box communicating at one end thereof, an outlet flue communi eating at the other end thereof, and a series of pots closed to the heating gases in the passage and provided with means for efiecting discharge of distillate and adapted to be traversed along the passage and to close the open top thereof.

6. In an apparatus of the class described,

an open-ended, open-topped passage, a series of pots adapted to receive pitch and to be traversed along the passage, a fire-box, a flue beneath the passage communicating with the fire-box at one end and with the passage at intervals and at its other end, to provide "a gradually increasing temperature along-said passage, and a flue for withdrawing the products of combustion from the passage.

7. In an apparatus of the class described, a horizontal passage open at the top and at its ends, means for heating the passage, a series of pots adapted to travel through the passage, means for supporting said pots, means for traversing themv when supported along the passage, means on said pots for closing the top of the passage, and means for Supplying said passage with heat.

' 8. In an apparatus of. the class described,

a horizontal passage having closed sides and bottom but open top, means for heating the passage, a series of pets, means for supporting the pots for travel within the'passage, means continuously moving the pots along said passage, means for charging the pots I with pitch, and means for maintaining the ends. of the passage normally closed to prevent the escape of heated gases.

9. In an apparatus of the class described, -a horizontal passage closed at both sides and at the bottom, means for supporting a se-. ries of receptacles in the passage, means for supplying heated gases to the passage adj acent one end thereof, means for withdrawing such gases adjacent the other end of the passage, a series of pots adapted to be fed along the passage, said pots being provided with cooperating means for substantially closing the top of the passage.

10. In an apparatus of the class described, a horizontal passage having closed sides and bottom, a series of pots adapted to be moved progressively along the passage, said 25 passage intermediate its ends being of a size to permit the free passage of heatedgases about the pots, and at its ends of a size and conformation to substantially fit the pots to prevent the. passage of heated gases about the same, means adjacent one end of the passage for supplying it with heated ,products of combustion, and a flue communicating with said passage adjacent its opposite end for withdrawing the products ofcombustion. 11. In an apparatus of a horizontal pass-agehaving closed sides and bottom and an open top, a series of pots, means for sup ortlngthe-pots in the passage along which t ey may be progressively fed, thepassage' being of such transverse dimen- 4 sions-intermediate its ends as to permit the free circulation of heated gases to the pots but constructed atits ends to substantially 45' fit the transverse section of the pots, means --for supplyingheated products of combustion near one end of the passage-and withdrawing them adjacent the other ends, the

pots tgging provided with'cotiperating flanges to su tantially close the top opening'of the p se i 12. 11 an apparatus f the class described,

- a horizontal passage ving'closed sides and bottom and an open to a series of pots, means for supporting t e pots in the: pas sage along which they. may be progressively; fed, the passage being of such transverse dimensions intermediate its endsas to permit the free circulation of heated gases about the pots but constructed at its ends to substantially fit the transverse section of the pots, means for supplying heated products ofcombustion near one end of the passage and withdrawing them adjacent the other" end; the pots being provided with coiiperat- ,eae'

ing flanges to substantially close the top opening of the passage, strips extending along the tops of the side walls of the furnace and adapted to be adjusted toward the pots and to coiiperate with the flanges thereof to seal the top opening of the passage.

13. In an apparatus of the class described, a horizontal passage having closed sides and bottom and'an open top, a series of pots,

means for supporting the pots in the passage along which they may be progressively fed, the passage being of such transverse dimensions intermediate'its ends as to permit the free circulation of' heated gases about the pots but constructed at its ends to substantially fit the transverse section of the pots, means for supplying heated products of combustion near one end of the passage and withdrawing them adjacent the other ends, the pots being provided with coiiperating flanges to substantially close the top opening of the passage, sectional strips extending along the tops of the side walls of the furnace and adapted to be adjusted toward the pots and to coiiperate with the flanges thereof to seal the top opening ofthe passa e.

I4. In an apparatus of the class described, a passage having closed sidewalls and bottom, means for movably supporting a series. of pots Within the passage, means for sup plying the passage with heated gases and withdrawing the gases therefrom, and means for progressively moving the pots through said passage. the class described,

15. In an apparatus of the class described, a passage having closed bottom and side walls, means for heating the passage, a series of coking pots, a support for the pots above the passage and along which the pots are movable longitudinally of the passage,

trolleys by which the pots are suspended from said support, a chain movable longitudinally of the passage and arran edv adjacent the said support, and means or connecting the trolleys to the chain;

16. In an apparatus of the class described, a passage having closed bottom and .side

walls, means for heating the passage, a series of coking pots, a support for the pots above'the passage and along which the pots are movable longitudinallyof the passage, trolleys by which the pots are suspended from said support, a chain movable longi-, .tudinally of the passage and arran ed adjacent thesaid support, and means or connecting the trolleys to the chain permitting the advance of the trolleys with reference to the chain but preventing .the lagging thereof. 4

17. In an apparatus of the classvdescribed,

a passage, means for heating the passage, a

series of pots for containing pitch to be coked, movable along the assage, means for supporting and moving t e pots along the' passage, a trough extending along the passage, and means for conveying gases and vapor from the pots to said trough.

18. In an apparatus of the class described, a passage having closedside walls and bottom, a series of pitch pots, means for supporting and moving said pitch pots along the passage, an extension formed on the passage at one end thereof and a door in said extension pivoted at its bottom to normally close the passage and counterbalanced to yield to the movement of the pitch pots past it, and then to close the passage.

19. In an apparatus of the class described, a passage having closed bottom and side walls, a series of pitch pots, means for supporting and moving said pitch pots through the passage, a tank for maintaining a supply of pitch, means for drawing the pitch from said tank into the several pitch pots, means for supplying the passage with heated products of combustion near one end thereof, a flue for conducting away the products of combustion near the other end of the passage, a heating chamber surrounding the supply tank with which the last said flue communicates, and means for conducting the products of combustion from said heating chamber.

20. In an apparatus of the class described, a passage having closed side and bottom walls, means for supplying said passage with heated products of combustion and for withdrawing such products therefrom, a series of pitch pots, an endless track, a portion of which extends immediately above said passage, trolleys on said track adapted to be connected to the respective pitch pots for supporting the same in the passage, an endless chain also mounted above the passage and means for engaging the trolleys to the chain and moving them along the passage, and means for driving said chain,

21. In an apparatus of the class described, a passage, means for heating the same, a series of pitch pots movable along the passage, an endless track extending partially above and longitudinally of said passage, trolleys on said track, means for supporting the respective pots from said trolleys, means for feeding the trolleys along the track, means located at the end of the passage for receiving and supporting the pots when disengaged from their respective trolleys, and means for dumping the pots.'

22. In an apparatus of the class described, a passage, means for heating the same, a series of pitch pots movable along the passage, an endless track extending partially above and longitudinally of said passage, trolleys on said track, means for supporting the respective pots from said trolleys, means for feeding the trolleys along the track, a corset adapted to receive and support the several pots located at the outlet .end of the passage, means for suspending the corset and for raising and lowering the same, and means for inverting the corset to dump the pot. i

23. In an apparatus of the class described, a passage, means for heating the same, a series of pitch pots movable along the passage, an endless track extending partially above and longitudinally of said passage, trolleys on said track, means for supporting the respective pots from said trolleys, means for feeding the trolleys along the track, a corset for receiving and supporting the pot, means for lockin the pot to the corset, means for supportlng and raising and lowering the corset, and means for reversing the same to dump the pots.

24. In an apparatus of the class described, a passage, means for heating the same, a series of pitch pots movable along the passage, an endless track extending partially above and longitudinally of said passage, trolleys on said track, means for supporting the respective pots from said trolleys, means for feeding the trolleys along the track, a corset for receiving and supporting a pot, means for locking the pot to the .corset, cables from which said corset is suspended attached to the upper end thereof and connected to a Windlass, a cable attached to the lower end of the corset and adapted to support the same in a position to dump the pot contained therein. i

25. In an apparatus of the class described, a track, a trolley on said track for supporting a pitch pot, said trolley comprising a bridge member, a pair of transverse bars on said bridge, one of such bars being stationary and the other ivoted to said bridge, and links connecting t e outer ends of said bars to a pitch pot for supporting the same.

26. In an apparatus of the class described, a heating passage, a series of pitch pots adapted andarranged to be fed along the passage, a cover for each said pot, a trough arranged adjacent and parallel to the passage, and aconduit from each cover dipping into said trough to convey gases and vapors from the pot to the trough.

27. In an apparatus of the class described, a passage, means for supporting and moving pitch pots along the passage, pitch pots each having a cover, a trough arranged parallel to the passage, conduits for the gas and vapors of distillation connected to the respective covers of the pitch pots, and a hood within the trough there being means on each conduit to discharge the gases therefrom beneath the said hood.

28. In anapparatus of the class described, a heating passage, a series of pitch pots movable along the passage, a trough extending parallel to said passage, a cover for each pitch pot, a riser connected to each cover, a tubular section pivoted to each riser and 

